poly_int: GET_MODE_PRECISION

This patch changes GET_MODE_PRECISION from an unsigned short
to a poly_uint16.

2018-01-03  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayward  <alan.hayward@arm.com>
	    David Sherwood  <david.sherwood@arm.com>

gcc/
	* machmode.h (mode_precision): Change from unsigned short to
	poly_uint16_pod.
	(mode_to_precision): Return a poly_uint16 rather than an unsigned
	short.
	(GET_MODE_PRECISION): Return a constant if ONLY_FIXED_SIZE_MODES,
	or if measurement_type is not polynomial.
	(HWI_COMPUTABLE_MODE_P): Turn into a function.  Optimize the case
	in which the mode is already known to be a scalar_int_mode.
	* genmodes.c (emit_mode_precision): Change the type of mode_precision
	from unsigned short to poly_uint16_pod.  Use ZERO_COEFFS for the
	initializer.
	* lto-streamer-in.c (lto_input_mode_table): Use bp_unpack_poly_value
	for GET_MODE_PRECISION.
	* lto-streamer-out.c (lto_write_mode_table): Use bp_pack_poly_value
	for GET_MODE_PRECISION.
	* combine.c (update_rsp_from_reg_equal): Treat GET_MODE_PRECISION
	as polynomial.
	(try_combine, find_split_point, combine_simplify_rtx): Likewise.
	(expand_field_assignment, make_extraction): Likewise.
	(make_compound_operation_int, record_dead_and_set_regs_1): Likewise.
	(get_last_value): Likewise.
	* convert.c (convert_to_integer_1): Likewise.
	* cse.c (cse_insn): Likewise.
	* expr.c (expand_expr_real_1): Likewise.
	* lra-constraints.c (simplify_operand_subreg): Likewise.
	* optabs-query.c (can_atomic_load_p): Likewise.
	* optabs.c (expand_atomic_load): Likewise.
	(expand_atomic_store): Likewise.
	* ree.c (combine_reaching_defs): Likewise.
	* rtl.h (partial_subreg_p, paradoxical_subreg_p): Likewise.
	* rtlanal.c (nonzero_bits1, lsb_bitfield_op_p): Likewise.
	* tree.h (type_has_mode_precision_p): Likewise.
	* ubsan.c (instrument_si_overflow): Likewise.

gcc/ada/
	* gcc-interface/misc.c (enumerate_modes): Treat GET_MODE_PRECISION
	as polynomial.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>

From-SVN: r256198

1 files changed, 42 insertions, 6 deletions

diff --git a/gcc/machmode.h b/gcc/machmode.h
index b97e046..99ffbb7 100644
--- a/gcc/machmode.h
+++ b/gcc/machmode.h
@@ -23,7 +23,7 @@ along with GCC; see the file COPYING3.  If not see
 typedef opt_mode<machine_mode> opt_machine_mode;
 
 extern CONST_MODE_SIZE unsigned short mode_size[NUM_MACHINE_MODES];
-extern const unsigned short mode_precision[NUM_MACHINE_MODES];
+extern const poly_uint16_pod mode_precision[NUM_MACHINE_MODES];
 extern const unsigned char mode_inner[NUM_MACHINE_MODES];
 extern const poly_uint16_pod mode_nunits[NUM_MACHINE_MODES];
 extern CONST_MODE_UNIT_SIZE unsigned char mode_unit_size[NUM_MACHINE_MODES];
@@ -535,7 +535,7 @@ mode_to_bits (machine_mode mode)
 
 /* Return the base GET_MODE_PRECISION value for MODE.  */
 
-ALWAYS_INLINE unsigned short
+ALWAYS_INLINE poly_uint16
 mode_to_precision (machine_mode mode)
 {
   return mode_precision[mode];
@@ -604,7 +604,30 @@ mode_to_nunits (machine_mode mode)
 
 /* Get the number of value bits of an object of mode MODE.  */
 
-#define GET_MODE_PRECISION(MODE) (mode_to_precision (MODE))
+#if ONLY_FIXED_SIZE_MODES
+#define GET_MODE_PRECISION(MODE) \
+  ((unsigned short) mode_to_precision (MODE).coeffs[0])
+#else
+ALWAYS_INLINE poly_uint16
+GET_MODE_PRECISION (machine_mode mode)
+{
+  return mode_to_precision (mode);
+}
+
+template<typename T>
+ALWAYS_INLINE typename if_poly<typename T::measurement_type>::type
+GET_MODE_PRECISION (const T &mode)
+{
+  return mode_to_precision (mode);
+}
+
+template<typename T>
+ALWAYS_INLINE typename if_nonpoly<typename T::measurement_type>::type
+GET_MODE_PRECISION (const T &mode)
+{
+  return mode_to_precision (mode).coeffs[0];
+}
+#endif
 
 /* Get the number of integral bits of an object of mode MODE.  */
 extern CONST_MODE_IBIT unsigned char mode_ibit[NUM_MACHINE_MODES];
@@ -863,9 +886,22 @@ extern void init_adjust_machine_modes (void);
   (targetm.truly_noop_truncation (GET_MODE_PRECISION (MODE1), \
 				  GET_MODE_PRECISION (MODE2)))
 
-#define HWI_COMPUTABLE_MODE_P(MODE) \
-  (SCALAR_INT_MODE_P (MODE) \
-   && GET_MODE_PRECISION (MODE) <= HOST_BITS_PER_WIDE_INT)
+/* Return true if MODE is a scalar integer mode that fits in a
+   HOST_WIDE_INT.  */
+
+inline bool
+HWI_COMPUTABLE_MODE_P (machine_mode mode)
+{
+  machine_mode mme = mode;
+  return (SCALAR_INT_MODE_P (mme)
+	  && mode_to_precision (mme).coeffs[0] <= HOST_BITS_PER_WIDE_INT);
+}
+
+inline bool
+HWI_COMPUTABLE_MODE_P (scalar_int_mode mode)
+{
+  return GET_MODE_PRECISION (mode) <= HOST_BITS_PER_WIDE_INT;
+}
 
 struct int_n_data_t {
   /* These parts are initailized by genmodes output */